Evaluation index combination weight-based embankment slope stability comprehensive evaluation method

Abstract

The invention discloses an embankment slope stability comprehensive evaluation method based on evaluation index combination weights, and belongs to the technical field of embankment slope stability analysis methods.According to the scheme, after a qualitative and quantitative slope stability evaluation index framework is constructed, the qualitative and quantitative weights of evaluation indexes are obtained through calculation based on AHP and EWM; obtaining a combined weight considering expert experience and index information through GT; and finally, the stability of the embankment slope relying on the project is evaluated in combination with the index framework and the combined weight, on one hand, expert experience is considered, and on the other hand, fuzzy information contained in the index is also considered, so that the calculated index weight value can better reflect the information contained in the index, qualitative and quantitative factors can be more comprehensively considered, and the stability of the embankment slope is improved. The obtained weight value is more accurate, and new technical enlightenment is brought to stability evaluation of the embankment slope.

Description

Technical Field

[0001] The invention relates to the technical field of embankment slope stability, in particular to the optimization of stability analysis methods. Background Art

[0002] Embankment slope instability is one of the common geological disasters in highway projects. It is very easy to cause huge economic losses and casualties after the disaster occurs. Therefore, the stability evaluation of embankment slopes is crucial for disaster prevention and control. The slope stability problem is a multi-factor, uncertain nonlinear problem. As a macroscopic manifestation of the internal mechanical mechanism, the slope instability deformation shows complex nonlinear evolution characteristics. The complex geological environment and external disturbances make it impossible to quantify the multi-factor influencing mechanism. Mechanical phenomena and mechanical parameters also have random uncertainties. There is a certain uncertainty and one-sidedness when obtaining quantitative parameter indicators, which cannot fully reflect the stability of the slope. At present, the stability evaluation of embankment slopes, especially the weight calculation of risk influencing factor indicators, either relies solely on expert experience or only through theoretical calculations, ignoring qualitative factors, and failing to take into account both qualitative and quantitative factors, resulting in inaccurate weight calculations and incomplete consideration of factors. Summary of the invention

[0003] In view of at least one of the above technical problems, the present invention provides a comprehensive evaluation method for embankment slope stability based on evaluation index combination weights, including a three-level embankment slope stability evaluation index system, establishing a qualitative and quantitative evaluation index framework; then calculating the qualitative and quantitative weights of the evaluation indexes through AHP and EWM, and obtaining the combination weights considering expert experience and index information based on GT; finally, combining the index framework and the combination weights to evaluate the embankment slope stability of the supporting project, the specific technical scheme is as follows:

[0004] A comprehensive evaluation method for embankment slope stability based on combined weights of evaluation indicators comprises the following steps: S1, analyzing the influencing factors of embankment slope stability;

[0005] S2, constructing the evaluation index framework of slope stability;

[0006] S3, the subjective weights of the evaluation indicators are calculated based on AHP, and the objective weights of the evaluation indicators are calculated based on EWM;

[0007] S4, obtain the combined weight of the evaluation indicators through GT;

[0008] S5, comprehensive evaluation of embankment slope stability.

[0009] In some embodiments of the present disclosure, in step S1, the influencing factors are constructed into an evaluation index set, and the evaluation index set is divided into criterion layers including slope foundation topography factors, slope foundation engineering geological characteristic factors, hydrological condition factors and engineering factors.

[0010] In some embodiments of the present disclosure, the evaluation index set of the criterion layer is further refined to establish an index layer; wherein the topographic and geomorphological factors of the slope foundation include slope foundation morphology factors, gully development and cutting degree factors, and vegetation coverage factors; the engineering geological characteristic factors of the slope foundation include rock and soil type factors, slope structure factors, structural surface development degree factors, rock and soil weathering degree factors, and horizontal seismic acceleration factors; the hydrological condition factors include daily maximum rainfall factors, saturated water content factors, groundwater corrosiveness factors, permeability coefficient factors, and groundwater depth factors; the engineering factors include excavation slope factors, support quality factors, drainage effect factors, excavation slope factors, filling height factors, layer thickness factors, compaction degree factors, roadbed top surface width factors, filler cohesion factors, and filler internal friction angle factors.

[0011] In some embodiments of the present disclosure, the step S2 is to classify the embankment slope stability into multiple evaluation levels qualitatively or quantitatively in combination with the slope stability coefficient.

[0012] In some embodiments of the present disclosure, the evaluation level is a qualitative classification of the embankment slope stability: level I represents very stable, level II represents relatively stable, level III represents basically stable, and level IV represents very stable.

[0013] In some embodiments of the present disclosure, the quantitative standard of level I is [0, 0.25), and the corresponding treatment measure is normal construction; the quantitative standard of level II is [0.25, 0.5), and the corresponding treatment measure is normal construction; the quantitative standard of level III is [0.5, 0.75), and the corresponding treatment measure is normal construction; the quantitative standard of level IV is [0.75, 1.0], and the corresponding treatment measure is normal construction.

[0014] In some embodiments of the present disclosure, when calculating the subjective weight of the evaluation index based on AHP in step S3:

[0015] The “1-9 scale method” is used to calculate the relative importance of evaluation indicators;

[0016] Afterwards, the consistency index CR is calculated based on the eigenvector of the judgment matrix. When CR is less than 0.1, the consistency of the judgment matrix meets the requirements;

[0017] Finally, the weight value of the evaluation index is obtained by normalizing the eigenvector of the judgment matrix;

[0018] The normalized evaluation index weight value must satisfy the following formula 1:

[0019]

[0020] In formula 1: i represents the subjective weight value of the i-th evaluation index, and n represents the number of evaluation indicators.

[0021] In some embodiments of the present disclosure, when the EWM calculates the objective weight of the evaluation index in step S3:

[0022] Construct the initial evaluation matrix and normalize it;

[0023] Then, the weights of the evaluation indicators are calculated and the weight matrix is ​​constructed;

[0024] Finally, the entropy value of the evaluation index is calculated and normalized to determine the relative weight of the evaluation index;

[0025] Among them, the calculation formula of the proportion of evaluation indicators is as follows:

[0026]

[0027] In formula 2: B ij represents the weight of the i-th evaluation index of the j-th evaluation object; r ij represents the normalized value, and m represents the number of evaluation objects;

[0028] The entropy value calculation formula of the evaluation index is as follows:

[0029]

[0030] In formula 3: A i Represents the entropy value of the i-th evaluation index;

[0031] The relative weight calculation formula of the evaluation index is as follows:

[0032]

[0033] In formula 4: i Represents the objective weight value of the i-th evaluation indicator.

[0034] In some embodiments of the present disclosure, in step S4, the method for calculating the combined weight value based on GT is:

[0035] L1, construction of evaluation index weight vector set;

[0036] L2, linear combination of evaluation index weights;

[0037] L3, linear combination coefficient optimization, and solving Nash equilibrium point;

[0038] L4, normalize the linear combination coefficients to obtain the combination coefficients.

[0039] In some embodiments of the present disclosure, the calculation formula of the evaluation index combination weight value is as follows:

[0040] C i =α s ω i +α o δ i 〈Formula 5〉;

[0041] In formula 5: C i Represents the combined weight of the i-th evaluation index; α s With α o Represent the subjective and objective weight combination coefficients respectively.

[0042] Compared with the prior art, the above-mentioned comprehensive evaluation method for embankment slope stability based on the combined weight of evaluation indicators has the following beneficial effects:

[0043] 1. This technical solution constructs a qualitative and quantitative slope stability evaluation index framework, calculates the qualitative and quantitative weights of the evaluation index based on AHP and EWM, and obtains the combined weights that consider expert experience and index information through GT; finally, the stability of the embankment slope based on the project is evaluated by combining the index framework and the combined weights. On the one hand, it considers the expert experience, and on the other hand, it takes into account the fuzzy information contained in the index. Therefore, the calculated index weight value can better reflect the information contained in the index, and can more comprehensively consider qualitative and quantitative factors, and the obtained weight value is more accurate;

[0044] 2. It provides a reference for the improvement of embankment slopes, improves stability, ensures the effect of ecological restoration, and brings new technical inspiration to related projects. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a flow chart of embankment slope stability evaluation based on combined weights of evaluation indicators in the present invention;

[0046] Figure 2 It is a schematic diagram of the comprehensive evaluation index set for embankment slope stability;

[0047] Figure 3 It is a schematic diagram of the comparison of evaluation index weight values. DETAILED DESCRIPTION

[0048] In order to better understand the purpose, structure and function of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below. It should be noted that, unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present application. The terms used herein in this application are only for the purpose of describing specific embodiments and are not intended to limit the present application. The terms "including" and "provided with" in this application and any variations thereof are open-ended and are intended to cover non-exclusive inclusions.

[0049] As shown in the attached figure Figures 1 to 3 As shown, an embodiment of a comprehensive evaluation method for embankment slope stability based on the combined weight of evaluation indicators is provided in this technical solution. The overall engineering route of this embodiment is in the direction of northeast-southwest. The starting and ending pile numbers of the project are K92+700~K105+361.073, the main line is 12.661km long, and the construction standard of a two-way four-lane expressway is adopted. The design speed is 120km / h, the integral roadbed is 26.5m wide, the half-width of the separated roadbed is 13.25m, and the asphalt concrete pavement structure is adopted. The project is located south of the Tropic of Cancer and belongs to the southern subtropical monsoon climate. There is a lot of precipitation and high humidity in the region. The annual precipitation is between 1500-2100mm and the rainy season is long. Among them, the eighth-level fill embankment in the section of K93+640~K94+875.94 is the controlling project of this project. The slope length is 236.0m, the embankment slope height is 64.5m, and the maximum fill height is 3.3m. The strata in the valley are mainly rock (fully weathered), rock (strongly weathered), and rock (moderately weathered). The first level of the embankment is 8 meters high with a slope of 1:1.5; the second level is 8 meters high with a slope of 1:1.75; the third to seventh levels are 8 meters high with a slope of 1:2; the eighth level is 8.8 meters high with a slope of 1:2. After the project started, due to the influence of heavy rainfall, the slope surface suffered from varying degrees of fine gully and shallow gully erosion and gully erosion damage, which brought major challenges to the smooth implementation of the project and the subsequent driver and passenger safety.

[0050] This method mainly includes the following steps:

[0051] S1, analyze the factors affecting the stability of embankment slopes; the selection of comprehensive, reasonable and accurate evaluation indicators is the basis for comprehensive evaluation of slope stability. To this end, combined with literature research, engineering case analysis, expert experience and other methods, the evaluation index set constructed is as follows Figure 2 As shown;

[0052] Among them, the index set is divided into three levels. The first level is the target layer, that is, the stability of the embankment slope; the second level is the criterion layer that affects the stability of the embankment slope, and the evaluation index set is divided into the criterion layer including the topographic factors of the slope foundation, the engineering geological characteristics of the slope foundation, the hydrological conditions and the engineering factors;

[0053] The evaluation index set of the criterion layer is further refined to establish an index layer; wherein the topographic factors of the slope foundation include slope foundation morphology factors, gully development and cutting degree factors and vegetation coverage factors; the engineering geological characteristic factors of the slope foundation include rock and soil type factors, slope structure factors, structural surface development degree factors, rock and soil weathering degree factors and horizontal earthquake acceleration factors; the hydrological condition factors include daily maximum rainfall factors, saturated water content factors, groundwater erosion factors, permeability coefficient factors and groundwater depth factors; the engineering factors include excavation slope factors, support quality factors, drainage effect factors, excavation slope factors, filling height factors, layer thickness factors, compaction factors, roadbed top surface width factors, filler cohesion factors and filler internal friction angle factors;

[0054] S2, constructing an evaluation index framework for slope stability; in this embodiment, the step S2 is to combine the slope stability coefficient to qualitatively or quantitatively divide the embankment slope stability into multiple evaluation levels. In this embodiment, the embankment slope stability can be qualitatively divided into: level I represents very stable, level II represents relatively stable, level III represents basically stable, and level IV represents very stable.

[0055] The quantitative standard of the level I is [0, 0.25), and the corresponding treatment measure is normal construction; the quantitative standard of the level II is [0.25, 0.5), and the corresponding treatment measure is normal construction; the quantitative standard of the level III is [0.5, 0.75), and the corresponding treatment measure is normal construction; the quantitative standard of the level IV is [0.75, 1.0], and the corresponding treatment measure is normal construction; based on this, the evaluation levels constructed are shown in Table 1 below:

[0056] Table 1 Evaluation indicators and grading standards

[0057] Rating Qualitative criteria Quantitative Standards Corresponding measures Level I Very stable, landslides are likely to be small [0，0.25) Normal construction Level II Relatively stable, landslide may be small [0.25，0.5) Regular monitoring Level III Basically stable, landslide may be moderate [0.5，0.75) Recommended measures to strengthen monitoring Level IV Very unstable, landslides may be large [0.75，1.0] Measures must be taken to strengthen monitoring

[0058] The stability corresponding to each indicator is shown below:

[0059] (1) Slope foundation topography. Slope foundation topography mainly includes slope foundation morphology, gully development and cutting degree, and vegetation coverage rate. Among them, the foundation morphology is further divided into concave slope, straight slope, convex slope and "S"-shaped slope. Convex slope and "S"-shaped slope have stress concentration, resulting in poor embankment slope stability. "S"-shaped slope has more stress concentration points and the worst stability; the more serious the gully development and cutting degree, the worse the embankment slope stability; the higher the vegetation coverage rate, the better the embankment slope stability.

[0060] (2) Engineering geological characteristics of slope foundation. The engineering geological characteristics of slope foundation mainly include rock and soil type, slope structure, degree of structural surface development, degree of rock and soil weathering, and horizontal seismic acceleration. Among them, the rock and soil type is further divided into four types: hard rock, well-cemented medium-hard rock, poorly-cemented medium-hard rock, and weak rock or loose rock and soil. The corresponding embankment slope stability gradually decreases; the slope structure is further divided into homogeneous structure, block structure, layered structure, and loose structure. The corresponding embankment slope stability gradually decreases; the embankment slope stability is negatively correlated with the degree of structural surface development, degree of rock and soil weathering, and horizontal seismic acceleration, that is, the higher the degree of structural surface development, degree of rock and soil weathering, and horizontal seismic acceleration, the worse the embankment slope stability.

[0061] (3) Hydrological conditions. Hydrological conditions mainly include daily maximum rainfall, saturated water content, groundwater corrosivity, permeability coefficient and groundwater depth. Among them, rainfall will cause the groundwater level to rise and the mechanical properties of rock and soil to change, which in turn affects the stability of the embankment slope. The greater the daily maximum rainfall, the higher the probability of embankment slope instability and the larger the scale; there is a significant negative correlation between the stability of the embankment slope and the saturated water content, groundwater corrosivity, permeability coefficient and groundwater depth, that is, the higher the saturated water content, the stronger the groundwater corrosivity, the greater the permeability coefficient and the deeper the groundwater depth, the worse the stability of the embankment slope.

[0062] (4) Engineering factors. Engineering factors mainly include excavation slope, support quality, drainage effect, excavation slope, filling height, layer thickness, compaction, roadbed top surface width, number of slope foundation sloping treatments, filler cohesion and filler internal friction angle. Among them, the stability of the embankment slope is positively correlated with the excavation slope, filling height and layer thickness, that is, the smaller the excavation slope, filling height and layer thickness, the better the embankment slope stability; the stability of the embankment slope is positively correlated with the excavation slope, compaction and roadbed top surface width, that is, the greater the excavation slope, the higher the compaction and the wider the roadbed top surface, the better the embankment slope stability; the better the support quality and the better the drainage effect, the better the embankment slope stability; the physical and mechanical properties of the filler also affect the stability of the embankment slope. When the filler cohesion and internal friction angle are larger and the filler shear strength is higher, the embankment slope stability is better.

[0063] The evaluation index classification standards are shown in Table 2 below:

[0064] Table 2 Evaluation index classification standards

[0065]

[0066]

[0067]

[0068] S3, the subjective weights of the evaluation indicators are calculated based on AHP, and the objective weights of the evaluation indicators are calculated based on EWM;

[0069] The analytic hierarchy process is a classic hierarchical weight analysis method widely used in multi-level decision-making problems. It decomposes the decision-making problem in order according to the target layer, criterion layer, and indicator layer, and then calculates the weight of each layer of indicators based on the judgment matrix obtained from expert experience. Finally, the weight of each layer of indicators relative to the target layer is determined by weighted summation. Therefore, AHP can be used to calculate the subjective weight of evaluation indicators;

[0070] In some embodiments of the present disclosure, when calculating the subjective weight of the evaluation index based on AHP in step S3:

[0071] The “1-9 scale method” is used to calculate the relative importance of evaluation indicators;

[0072] Afterwards, the consistency index CR is calculated based on the eigenvector of the judgment matrix. When CR is less than 0.1, the consistency of the judgment matrix meets the requirements;

[0073] Finally, the weight value of the evaluation index is obtained by normalizing the eigenvector of the judgment matrix;

[0074] The normalized evaluation index weight value must satisfy the following formula 1:

[0075]

[0076] In formula 1: i represents the subjective weight value of the i-th evaluation index, and n represents the number of evaluation indicators.

[0077] The entropy weight method is an objective weighting method widely used in multi-index comprehensive evaluation. It uses information entropy to calculate the entropy value based on the degree of index variation, and in turn corrects the weight of the evaluation index, thereby objectively calculating the weight value of each evaluation index. The larger the entropy value, the lower the discreteness of the index, indicating that the evaluation index has less impact on the target and the smaller the weight value; conversely, the smaller the entropy value, the larger the weight value;

[0078] In some embodiments of the present disclosure, when the EWM calculates the objective weight of the evaluation index in step S3:

[0079] Construct the initial evaluation matrix and normalize it;

[0080] Then, the weights of the evaluation indicators are calculated and the weight matrix is ​​constructed;

[0081] Finally, the entropy value of the evaluation index is calculated and normalized to determine the relative weight of the evaluation index;

[0082] Among them, the calculation formula of the proportion of evaluation indicators is as follows:

[0083]

[0084] In formula 2: B ij represents the weight of the i-th evaluation index of the j-th evaluation object; r ij represents the normalized value, and m represents the number of evaluation objects;

[0085] The entropy value calculation formula of the evaluation index is as follows:

[0086]

[0087] In formula 3: A i Represents the entropy value of the i-th evaluation index;

[0088] The relative weight calculation formula of the evaluation index is as follows:

[0089]

[0090] In formula 4: i Represents the objective weight value of the i-th evaluation indicator.

[0091] S4, obtain the combined weight of the evaluation indicators through GT;

[0092] When determining the weight values ​​of evaluation indicators, the weight values ​​obtained by the hierarchical analysis method are highly subjective, easily affected by the personal preferences of experts, and are one-sided and lack subjectivity. The entropy weight method focuses on the information of the evaluation indicators themselves, avoiding the influence of personal preferences of experts, but ignores the ambiguity of qualitative indicators and cannot consider the importance characteristics of the indicators themselves. Therefore, GT is used to combine subjective and objective weights to obtain a more comprehensive combined weight value;

[0093] In some embodiments of the present disclosure, in step S4, the method for calculating the combined weight value based on GT is:

[0094] L1, construction of evaluation index weight vector set;

[0095] L2, linear combination of evaluation index weights;

[0096] L3, linear combination coefficient optimization, and solving Nash equilibrium point;

[0097] There are many ways to solve Nash equilibrium points, including graphical methods, algebraic methods, fixed point theorems, etc. For simple game models, you can directly observe the payoff matrix of the participants through graphical methods to find the strategy combination that meets the Nash equilibrium conditions. For complex game models, you need to use mathematical tools such as algebraic methods or fixed point theorems to solve them. In addition, with the development of computer technology, numerical simulation and algorithm optimization have also become important means to solve Nash equilibrium points. For example, in the field of machine learning, the Nash equilibrium point can be gradually approached through iterative algorithms.

[0098] L4, normalize the linear combination coefficients to obtain the combination coefficients;

[0099] For qualitative data, the expert questionnaire method can be used to combine expert engineering experience and theoretical knowledge to evaluate qualitative data. The evaluation standard adopts the (0-1) scoring method, that is, a value between 0 and 1 is used to express the importance of qualitative data. 0 means that the importance of the data can be ignored, and 1 means that the importance of the data is the greatest. The larger the value, the more important the qualitative data, and vice versa.

[0100] For quantitative data, the minimum and maximum values ​​of the quantitative data are first used to normalize the data. The calculation formula is as follows: 6, which is convenient for data fusion with the qualitative data evaluation results;

[0101]

[0102] In Formula 6: a represents the specific value of the quantitative data; min represents the minimum value of the data; max represents the maximum value of the data; b represents the normalized value of the quantitative data, that is, the value range of b is (0-1). When a takes the minimum value, the normalized b value is 0, indicating that the importance of the data can be ignored; when a takes the maximum value, the normalized b value is 1, indicating that the importance of the data is the greatest.

[0103] In some embodiments of the present disclosure, the calculation formula of the evaluation index combination weight value is as follows:

[0104] C i =α s ω i +α o δ i 〈Formula 5〉;

[0105] In formula 5: C i Represents the combined weight of the i-th evaluation index; α s With α o Represent the subjective and objective weight combination coefficients respectively.

[0106] S5, comprehensive evaluation of embankment slope stability.

[0107] The subjective weight of the evaluation index is calculated by the AHP method based on expert experience and passes the consistency test; the objective weight of the evaluation index is calculated by EWM; finally, the combined weight of the evaluation index is determined by GT. The calculation results are as follows: Figure 3 As shown. It can be seen that the indicator weight value determined based on GT is between the subjective weight value and the objective weight value; the subjective weight value calculated by AHP contains too many expert experience values, resulting in a large indicator weight value; the objective weight value calculated by EWM over-relies on the indicator value itself and ignores the fuzzy information contained in the data, resulting in a small indicator weight value; therefore, the indicator weight value calculated by AHP or EWM cannot fully consider the information contained in the indicator. Therefore, this study proposes a combined weight calculation method based on GT, which takes into account the expert experience on the one hand and the fuzzy information contained in the indicator on the other hand. Therefore, the calculated indicator weight value can better reflect the information contained in the indicator, and the evaluation results are more comprehensive and accurate.

[0108] Figure 3 The evaluation index data set is shown in Table 3 below. Combined with the combined weights of the evaluation indexes, the stability of the embankment slope is comprehensively evaluated. The calculation results show that the evaluation result of the embankment slope stability is 0.605, the grade is III, basically stable, the possibility of landslide during construction is medium, and it is recommended to take corresponding protective measures.

[0109] Table 3 Evaluation index dataset

[0110]

[0111]

[0112] When the support quality is improved from medium to very good, the evaluation result is reduced from 0.605 to 0.587, and the grade is still III, which is basically stable, and the possibility of landslide is medium; when the drainage effect is improved from medium to very good, the evaluation result is reduced from 0.605 to 0.591, and the grade is still III, which is basically stable, and the possibility of landslide is medium; when the filling height is reduced from 64.5m to 7.5m, the evaluation result is reduced from 0.605 to 0.574, and the grade is still III, which is basically stable, and the possibility of landslide is medium; when the compaction degree is increased from 93% to 96%, the evaluation result is reduced from 0.605 to 0.569, which is still III, which is basically stable, and the possibility of landslide is medium. The evaluation result is medium; when the internal friction angle of the filler increases from 28.4° to 45.6°, the evaluation result decreases from 0.605 to 0.598, and the grade is still III, which is basically stable, and the possibility of landslide is medium; when the support quality and drainage effect are improved from medium to very good, the filling height is reduced from 64.5m to 7.5m, the compaction degree is increased from 93% to 96%, and the internal friction angle of the filler is increased from 28.4° to 45.6°, the evaluation result decreases from 0.605 to 0.488, and the grade is improved to II, which is relatively stable and the possibility of landslide is small; therefore, in the subsequent embankment slope construction process, it is recommended to take a variety of protective measures to comprehensively reduce the risks of the slope construction process, thereby ensuring construction safety.

[0113] This technical solution constructs a qualitative and quantitative slope stability evaluation index framework, calculates the qualitative and quantitative weights of the evaluation index based on AHP and EWM, and obtains the combined weights that consider expert experience and index information through GT; finally, the stability of the embankment slope based on the project is evaluated by combining the index framework and the combined weights. On the one hand, it considers the expert experience, and on the other hand, it takes into account the fuzzy information contained in the index. Therefore, the calculated index weight value can better reflect the information contained in the index, and can more comprehensively consider qualitative and quantitative factors, and the obtained weight value is more accurate;

[0114] It provides a reference for the improvement of embankment slopes, improves stability, ensures the effect of ecological restoration, and brings new technical inspiration to related projects.

[0115] It can be understood that the above description is only for illustrating the specific implementation of the present application, but the protection scope of the present application is not limited thereto, and any changes or substitutions within the technical scope disclosed in the present application should be included in the disclosure scope of the present application.

Claims

1. A comprehensive evaluation method for embankment slope stability based on combined weights of evaluation indicators, characterized in that: The following steps are involved: S1, analyze the factors affecting the stability of embankment slope; S2, constructing the evaluation index framework of slope stability; S3, the subjective weights of the evaluation indicators are calculated based on AHP, and the objective weights of the evaluation indicators are calculated based on EWM; S4, obtain the combined weight of the evaluation indicators through GT; S5, comprehensive evaluation of embankment slope stability.

2. The comprehensive evaluation method for embankment slope stability based on combined weights of evaluation indicators according to claim 1 is characterized in that: In step S1, the influencing factors are used to construct an evaluation index set, and the evaluation index set is divided into a criterion layer including slope foundation topography factors, slope foundation engineering geological characteristic factors, hydrological condition factors and engineering factors.

3. The comprehensive evaluation method for embankment slope stability based on combined weights of evaluation indicators according to claim 2 is characterized in that: The evaluation index set of the criterion layer is further refined to establish an index layer; wherein the topographical and geomorphic factors of the slope foundation include slope foundation morphology factors, gully development and cutting degree factors and vegetation coverage factors; the engineering geological characteristic factors of the slope foundation include rock and soil type factors, slope structure factors, structural surface development degree factors, rock and soil weathering degree factors and horizontal earthquake acceleration factors; the hydrological condition factors include daily maximum rainfall factors, saturated water content factors, groundwater corrosiveness factors, permeability coefficient factors and groundwater depth factors; the engineering factors include excavation slope factors, support quality factors, drainage effect factors, excavation slope factors, filling height factors, layer thickness factors, compaction degree factors, roadbed top surface width factors, filler cohesion factors and filler internal friction angle factors.

4. The comprehensive evaluation method for embankment slope stability based on evaluation index combination weights according to claim 3 is characterized in that: The step S2 is to classify the embankment slope stability into multiple evaluation levels qualitatively or quantitatively in combination with the slope stability coefficient.

5. The comprehensive evaluation method for embankment slope stability based on combined weights of evaluation indicators according to claim 4 is characterized in that: The evaluation level is a qualitative classification of the embankment slope stability: Level I represents very stable, Level II represents relatively stable, Level III represents basically stable, and Level IV represents very stable.

6. The comprehensive evaluation method for embankment slope stability based on evaluation index combination weights according to claim 5 is characterized in that: The quantitative standard of level I is [0, 0.25), and the corresponding treatment measure is normal construction; the quantitative standard of level II is [0.25, 0.5), and the corresponding treatment measure is normal construction; the quantitative standard of level III is [0.5, 0.75), and the corresponding treatment measure is normal construction; the quantitative standard of level IV is [0.75, 1.0], and the corresponding treatment measure is normal construction.

7. The comprehensive evaluation method for embankment slope stability based on evaluation index combination weights according to claim 6 is characterized in that: When calculating the subjective weight of the evaluation index based on AHP in step S3: The "1-9 scale method" is used to calculate the relative importance of evaluation indicators; Afterwards, the consistency index CR is calculated based on the eigenvector of the judgment matrix. When CR is less than 0.1, the consistency of the judgment matrix meets the requirements; Finally, the weight value of the evaluation index is obtained by normalizing the eigenvector of the judgment matrix; The normalized evaluation index weight value must satisfy the following formula 1: In formula 1: i represents the subjective weight value of the i-th evaluation index, and n represents the number of evaluation indicators.

8. The comprehensive evaluation method for embankment slope stability based on combined weights of evaluation indicators according to claim 1 is characterized in that: When EWM calculates the objective weight of the evaluation index in step S3: Construct the initial evaluation matrix and normalize it; Then, the weights of the evaluation indicators are calculated and the weight matrix is ​​constructed; Finally, the entropy value of the evaluation index is calculated and normalized to determine the relative weight of the evaluation index; Among them, the calculation formula of the proportion of evaluation indicators is as follows: In formula 2: B ij represents the weight of the i-th evaluation index of the j-th evaluation object; r ij represents the normalized value, and m represents the number of evaluation objects; The entropy value calculation formula of the evaluation index is as follows: In formula 3: A i Represents the entropy value of the i-th evaluation index; The relative weight calculation formula of the evaluation index is as follows: In formula 4: i Represents the objective weight value of the i-th evaluation indicator.

9. The comprehensive evaluation method for embankment slope stability based on evaluation index combination weights according to claim 1 is characterized in that: In step S4, the method for calculating the combined weight value based on GT is: L1, construction of evaluation index weight vector set; L2, linear combination of evaluation index weights; L3, linear combination coefficient optimization, and solving Nash equilibrium point; L4, normalize the linear combination coefficients to obtain the combination coefficients.

10. The comprehensive evaluation method for embankment slope stability based on evaluation index combination weights according to claim 9 is characterized in that: The calculation formula of the combined weight value of the evaluation index is as follows: C i = α s ω i + α o δ i 〈Equation 5〉; In formula 5: C i Represents the combined weight of the i-th evaluation index; α s With α o Represent the subjective and objective weight combination coefficients respectively.

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